-- 创建 Tool C Session 表
-- 日期: 2025-12-06
-- 用途: 科研数据编辑器会话管理

CREATE TABLE IF NOT EXISTS dc_schema.dc_tool_c_sessions (
  id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
  user_id VARCHAR(255) NOT NULL,
  file_name VARCHAR(500) NOT NULL,
  file_key VARCHAR(500) NOT NULL,
  
  -- 数据元信息
  total_rows INTEGER NOT NULL,
  total_cols INTEGER NOT NULL,
  columns JSONB NOT NULL,
  encoding VARCHAR(50),
  file_size INTEGER NOT NULL,
  
  -- 时间戳
  created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
  updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
  expires_at TIMESTAMP NOT NULL
);

-- 创建索引
CREATE INDEX IF NOT EXISTS idx_dc_tool_c_sessions_user_id ON dc_schema.dc_tool_c_sessions(user_id);
CREATE INDEX IF NOT EXISTS idx_dc_tool_c_sessions_expires_at ON dc_schema.dc_tool_c_sessions(expires_at);

-- 添加注释
COMMENT ON TABLE dc_schema.dc_tool_c_sessions IS 'Tool C (科研数据编辑器) Session会话表';
COMMENT ON COLUMN dc_schema.dc_tool_c_sessions.file_key IS 'OSS存储路径: dc/tool-c/sessions/{timestamp}-{fileName}';
COMMENT ON COLUMN dc_schema.dc_tool_c_sessions.columns IS '列名数组 ["age", "gender", "diagnosis"]';
COMMENT ON COLUMN dc_schema.dc_tool_c_sessions.expires_at IS '过期时间（创建后10分钟）';